Return to strfmon.c CVS log

Up to [cvs.NetBSD.org] / src / lib / libc / stdlib

Pull up revision 1.6 (requested by mjf in ticket #1115).

Fix another integer overflow issue discovered by Maksymilian Arciemowicz.
On top of this, limit the range of getnumber to 0x00ffffff to make sure
that adding two of them does not cause an integer overflow.

/*	$NetBSD: strfmon.c,v 1.4.14.2 2008/04/07 13:14:22 jdc Exp $	*/

/*-
 * Copyright (c) 2001 Alexey Zelkin <phantom@FreeBSD.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 */

#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
__FBSDID("$FreeBSD: src/lib/libc/stdlib/strfmon.c,v 1.14 2003/03/20 08:18:55 ache Exp $");
#else
__RCSID("$NetBSD: strfmon.c,v 1.4.14.2 2008/04/07 13:14:22 jdc Exp $");
#endif
#endif /* LIBC_SCCS and not lint */

#if defined(__NetBSD__)
#include "namespace.h"
#include <monetary.h>
#endif

#include <sys/types.h>
#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <locale.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stddef.h>

/* internal flags */
#define	NEED_GROUPING		0x01	/* print digits grouped (default) */
#define	SIGN_POSN_USED		0x02	/* '+' or '(' usage flag */
#define	LOCALE_POSN		0x04	/* use locale defined +/- (default) */
#define	PARENTH_POSN		0x08	/* enclose negative amount in () */
#define	SUPRESS_CURR_SYMBOL	0x10	/* supress the currency from output */
#define	LEFT_JUSTIFY		0x20	/* left justify */
#define	USE_INTL_CURRENCY	0x40	/* use international currency symbol */
#define IS_NEGATIVE		0x80	/* is argument value negative ? */

/* internal macros */
#define PRINT(CH) do {						\
	if (dst >= s + maxsize) 				\
		goto e2big_error;				\
	*dst++ = CH;						\
} while (/* CONSTCOND */ 0)

#define PRINTS(STR) do {					\
	const char *tmps = STR;					\
	while (*tmps != '\0')					\
		PRINT(*tmps++);					\
} while (/* CONSTCOND */ 0)

#define GET_NUMBER(VAR)	do {					\
	VAR = 0;						\
	while (isdigit((unsigned char)*fmt)) {			\
		VAR *= 10;					\
		VAR += *fmt - '0';				\
		if (VAR > 0x00ffffff)				\
			goto e2big_error;			\
		fmt++;						\
	}							\
} while (/* CONSTCOND */ 0)

#define GRPCPY(howmany) do {					\
	int i = howmany;					\
	while (i-- > 0) {					\
		avalue_size--;					\
		*--bufend = *(avalue+avalue_size+padded);	\
	}							\
} while (/* CONSTCOND */ 0)

#define GRPSEP do {						\
	*--bufend = thousands_sep;				\
	groups++;						\
} while (/* CONSTCOND */ 0)

static void __setup_vars(int, char *, char *, char *, const char **);
static int __calc_left_pad(int, char *);
static char *__format_grouped_double(double, int *, int, int, int);

ssize_t
strfmon(char * __restrict s, size_t maxsize, const char * __restrict format,
    ...)
{
	va_list		ap;
	char 		*dst;		/* output destination pointer */
	const char 	*fmt;		/* current format poistion pointer */
	struct lconv 	*lc;		/* pointer to lconv structure */
	char		*asciivalue;	/* formatted double pointer */

	int		flags;		/* formatting options */
	int		pad_char;	/* padding character */
	int		pad_size;	/* pad size */
	int		width;		/* field width */
	int		left_prec;	/* left precision */
	int		right_prec;	/* right precision */
	double		value;		/* just value */
	char		space_char = ' '; /* space after currency */

	char		cs_precedes,	/* values gathered from struct lconv */
			sep_by_space,
			sign_posn,
			*currency_symbol;
	const char	*signstr;

	char		*tmpptr;	/* temporary vars */
	int		sverrno;

        va_start(ap, format);

	lc = localeconv();
	dst = s;
	fmt = format;
	asciivalue = NULL;
	currency_symbol = NULL;
	pad_size = 0;

	while (*fmt) {
		/* pass nonformating characters AS IS */
		if (*fmt != '%')
			goto literal;

		/* '%' found ! */

		/* "%%" mean just '%' */
		if (*(fmt+1) == '%') {
			fmt++;
	literal:
			PRINT(*fmt++);
			continue;
		}

		/* set up initial values */
		flags = (NEED_GROUPING|LOCALE_POSN);
		pad_char = ' ';		/* padding character is "space" */
		left_prec = -1;		/* no left precision specified */
		right_prec = -1;	/* no right precision specified */
		width = -1;		/* no width specified */
		value = 0;		/* we have no value to print now */

		/* Flags */
		while (/* CONSTCOND */ 1) {
			switch (*++fmt) {
				case '=':	/* fill character */
					pad_char = *++fmt;
					if (pad_char == '\0')
						goto format_error;
					continue;
				case '^':	/* not group currency  */
					flags &= ~(NEED_GROUPING);
					continue;
				case '+':	/* use locale defined signs */
					if (flags & SIGN_POSN_USED)
						goto format_error;
					flags |= (SIGN_POSN_USED|LOCALE_POSN);
					continue;
				case '(':	/* enclose negatives with () */
					if (flags & SIGN_POSN_USED)
						goto format_error;
					flags |= (SIGN_POSN_USED|PARENTH_POSN);
					continue;
				case '!':	/* suppress currency symbol */
					flags |= SUPRESS_CURR_SYMBOL;
					continue;
				case '-':	/* alignment (left)  */
					flags |= LEFT_JUSTIFY;
					continue;
				default:
					break;
			}
			break;
		}

		/* field Width */
		if (isdigit((unsigned char)*fmt)) {
			ptrdiff_t d = dst - s;
			GET_NUMBER(width);
			/* Do we have enough space to put number with
			 * required width ?
			 */

			if (d + width >= maxsize)
				goto e2big_error;
		}

		/* Left precision */
		if (*fmt == '#') {
			if (!isdigit((unsigned char)*++fmt))
				goto format_error;
			GET_NUMBER(left_prec);
		}

		/* Right precision */
		if (*fmt == '.') {
			if (!isdigit((unsigned char)*++fmt))
				goto format_error;
			GET_NUMBER(right_prec);
		}

		/* Conversion Characters */
		switch (*fmt++) {
			case 'i':	/* use internaltion currency format */
				flags |= USE_INTL_CURRENCY;
				break;
			case 'n':	/* use national currency format */
				flags &= ~(USE_INTL_CURRENCY);
				break;
			default:	/* required character is missing or
					   premature EOS */
				goto format_error;
		}

		if (currency_symbol)
			free(currency_symbol);
		if (flags & USE_INTL_CURRENCY) {
			currency_symbol = strdup(lc->int_curr_symbol);
			if (currency_symbol != NULL)
				space_char = *(currency_symbol+3);
		} else
			currency_symbol = strdup(lc->currency_symbol);

		if (currency_symbol == NULL)
			goto end_error;			/* ENOMEM. */

		/* value itself */
		value = va_arg(ap, double);

		/* detect sign */
		if (value < 0) {
			flags |= IS_NEGATIVE;
			value = -value;
		}

		/* fill left_prec with amount of padding chars */
		if (left_prec >= 0) {
			pad_size = __calc_left_pad((flags ^ IS_NEGATIVE),
							currency_symbol) -
				   __calc_left_pad(flags, currency_symbol);
			if (pad_size < 0)
				pad_size = 0;
		}

		asciivalue = __format_grouped_double(value, &flags,
				left_prec, right_prec, pad_char);
		if (asciivalue == NULL)
			goto end_error;		/* errno already set     */
						/* to ENOMEM by malloc() */

		/* set some variables for later use */
		__setup_vars(flags, &cs_precedes, &sep_by_space,
				&sign_posn, &signstr);

		/*
		 * Description of some LC_MONETARY's values:
		 *
		 * p_cs_precedes & n_cs_precedes
		 *
		 * = 1 - $currency_symbol precedes the value
		 *       for a monetary quantity with a non-negative value
		 * = 0 - symbol succeeds the value
		 *
		 * p_sep_by_space & n_sep_by_space
                 *
		 * = 0 - no space separates $currency_symbol
		 *       from the value for a monetary quantity with a
		 *	 non-negative value
		 * = 1 - space separates the symbol from the value
		 * = 2 - space separates the symbol and the sign string,
		 *       if adjacent.
                 *
		 * p_sign_posn & n_sign_posn
                 *
		 * = 0 - parentheses enclose the quantity and the
		 *	 $currency_symbol
		 * = 1 - the sign string precedes the quantity and the 
		 *       $currency_symbol
		 * = 2 - the sign string succeeds the quantity and the 
		 *       $currency_symbol
		 * = 3 - the sign string precedes the $currency_symbol
		 * = 4 - the sign string succeeds the $currency_symbol
                 *
		 */

		tmpptr = dst;

		while (pad_size-- > 0)
			PRINT(' ');

		if (sign_posn == 0 && (flags & IS_NEGATIVE))
			PRINT('(');

		if (cs_precedes == 1) {
			if (sign_posn == 1 || sign_posn == 3) {
				PRINTS(signstr);
				if (sep_by_space == 2)		/* XXX: ? */
					PRINT(' ');
			}

			if (!(flags & SUPRESS_CURR_SYMBOL)) {
				PRINTS(currency_symbol);

				if (sign_posn == 4) {
					if (sep_by_space == 2)
						PRINT(space_char);
					PRINTS(signstr);
					if (sep_by_space == 1)
						PRINT(' ');
				} else if (sep_by_space == 1)
					PRINT(space_char);
			}
		} else if (sign_posn == 1)
			PRINTS(signstr);

		PRINTS(asciivalue);

		if (cs_precedes == 0) {
			if (sign_posn == 3) {
				if (sep_by_space == 1)
					PRINT(' ');
				PRINTS(signstr);
			}

			if (!(flags & SUPRESS_CURR_SYMBOL)) {
				if ((sign_posn == 3 && sep_by_space == 2)
				    || (sep_by_space == 1
				    && (sign_posn == 0
				    || sign_posn == 1
				    || sign_posn == 2
				    || sign_posn == 4)))
					PRINT(space_char);
				PRINTS(currency_symbol); /* XXX: len */
				if (sign_posn == 4) {
					if (sep_by_space == 2)
						PRINT(' ');
					PRINTS(signstr);
				}
			}
		}

		if (sign_posn == 2) {
			if (sep_by_space == 2)
				PRINT(' ');
			PRINTS(signstr);
		}

		if (sign_posn == 0 && (flags & IS_NEGATIVE))
			PRINT(')');

		if (dst - tmpptr < width) {
			if (flags & LEFT_JUSTIFY) {
				while (dst - tmpptr < width)
					PRINT(' ');
			} else {
				pad_size = dst-tmpptr;
				memmove(tmpptr + width-pad_size, tmpptr,
				    (size_t) pad_size);
				memset(tmpptr, ' ', (size_t) width-pad_size);
				dst += width-pad_size;
			}
		}
	}

	PRINT('\0');
	va_end(ap);
	free(asciivalue);
	free(currency_symbol);
	return (dst - s - 1);	/* return size of put data except trailing '\0' */

e2big_error:
	errno = E2BIG;
	goto end_error;

format_error:
	errno = EINVAL;

end_error:
	sverrno = errno;
	if (asciivalue != NULL)
		free(asciivalue);
	if (currency_symbol != NULL)
		free(currency_symbol);
	errno = sverrno;
	va_end(ap);
	return (-1);
}

static void
__setup_vars(int flags, char *cs_precedes, char *sep_by_space,
		char *sign_posn, const char **signstr) {
	struct lconv *lc = localeconv();

	if ((flags & IS_NEGATIVE) && (flags & USE_INTL_CURRENCY)) {
		*cs_precedes = lc->int_n_cs_precedes;
		*sep_by_space = lc->int_n_sep_by_space;
		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->int_n_sign_posn;
		*signstr = (lc->negative_sign == '\0') ? "-"
		    : lc->negative_sign;
	} else if (flags & USE_INTL_CURRENCY) {
		*cs_precedes = lc->int_p_cs_precedes;
		*sep_by_space = lc->int_p_sep_by_space;
		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->int_p_sign_posn;
		*signstr = lc->positive_sign;
	} else if (flags & IS_NEGATIVE) {
		*cs_precedes = lc->n_cs_precedes;
		*sep_by_space = lc->n_sep_by_space;
		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->n_sign_posn;
		*signstr = (lc->negative_sign == '\0') ? "-"
		    : lc->negative_sign;
	} else {
		*cs_precedes = lc->p_cs_precedes;
		*sep_by_space = lc->p_sep_by_space;
		*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->p_sign_posn;
		*signstr = lc->positive_sign;
	}

	/* Set defult values for unspecified information. */
	if (*cs_precedes != 0)
		*cs_precedes = 1;
	if (*sep_by_space == CHAR_MAX)
		*sep_by_space = 0;
	if (*sign_posn == CHAR_MAX)
		*sign_posn = 0;
}

static int
__calc_left_pad(int flags, char *cur_symb) {

	char cs_precedes, sep_by_space, sign_posn;
	const char *signstr;
	int left_chars = 0;

	__setup_vars(flags, &cs_precedes, &sep_by_space, &sign_posn, &signstr);

	if (cs_precedes != 0) {
		left_chars += strlen(cur_symb);
		if (sep_by_space != 0)
			left_chars++;
	}

	switch (sign_posn) {
		case 1:
			left_chars += strlen(signstr);
			break;
		case 3:
		case 4:
			if (cs_precedes != 0)
				left_chars += strlen(signstr);
	}
	return (left_chars);
}

static int
get_groups(int size, char *grouping) {

	int	chars = 0;

	if (*grouping == CHAR_MAX || *grouping <= 0)	/* no grouping ? */
		return (0);

	while (size > (int)*grouping) {
		chars++;
		size -= (int)*grouping++;
		/* no more grouping ? */
		if (*grouping == CHAR_MAX)
			break;
		/* rest grouping with same value ? */
		if (*grouping == 0) {
			chars += (size - 1) / *(grouping - 1);
			break;
		}
	}
	return (chars);
}

/* convert double to ASCII */
static char *
__format_grouped_double(double value, int *flags,
			int left_prec, int right_prec, int pad_char) {

	char		*rslt;
	char		*avalue;
	int		avalue_size;
	char		fmt[32];

	size_t		bufsize;
	char		*bufend;

	int		padded;

	struct lconv	*lc = localeconv();
	char		*grouping;
	char		decimal_point;
	char		thousands_sep;

	int groups = 0;

	grouping = lc->mon_grouping;
	decimal_point = *lc->mon_decimal_point;
	if (decimal_point == '\0')
		decimal_point = *lc->decimal_point;
	thousands_sep = *lc->mon_thousands_sep;
	if (thousands_sep == '\0')
		thousands_sep = *lc->thousands_sep;

	/* fill left_prec with default value */
	if (left_prec == -1)
		left_prec = 0;

	/* fill right_prec with default value */
	if (right_prec == -1) {
                if (*flags & USE_INTL_CURRENCY)
                        right_prec = lc->int_frac_digits;
                else
                        right_prec = lc->frac_digits;

		if (right_prec == CHAR_MAX)	/* POSIX locale ? */
			right_prec = 2;
	}

	if (*flags & NEED_GROUPING)
		left_prec += get_groups(left_prec, grouping);

	/* convert to string */
	snprintf(fmt, sizeof(fmt), "%%%d.%df", left_prec + right_prec + 1,
	    right_prec);
	avalue_size = asprintf(&avalue, fmt, value);
	if (avalue_size < 0)
		return (NULL);

	/* make sure that we've enough space for result string */
	bufsize = strlen(avalue)*2+1;
	rslt = malloc(bufsize);
	if (rslt == NULL) {
		free(avalue);
		return (NULL);
	}
	memset(rslt, 0, bufsize);
	bufend = rslt + bufsize - 1;	/* reserve space for trailing '\0' */

	/* skip spaces at beggining */
	padded = 0;
	while (avalue[padded] == ' ') {
		padded++;
		avalue_size--;
	}

	if (right_prec > 0) {
		bufend -= right_prec;
		memcpy(bufend, avalue + avalue_size+padded-right_prec,
		    (size_t) right_prec);
		*--bufend = decimal_point;
		avalue_size -= (right_prec + 1);
	}

	if ((*flags & NEED_GROUPING) &&
	    thousands_sep != '\0' &&	/* XXX: need investigation */
	    *grouping != CHAR_MAX &&
	    *grouping > 0) {
		while (avalue_size > (int)*grouping) {
			GRPCPY(*grouping);
			GRPSEP;
			grouping++;

			/* no more grouping ? */
			if (*grouping == CHAR_MAX)
				break;

			/* rest grouping with same value ? */
			if (*grouping == 0) {
				grouping--;
				while (avalue_size > *grouping) {
					GRPCPY(*grouping);
					GRPSEP;
				}
			}
		}
		if (avalue_size != 0)
			GRPCPY(avalue_size);
		padded -= groups;

	} else {
		bufend -= avalue_size;
		memcpy(bufend, avalue+padded, (size_t) avalue_size);
		if (right_prec == 0)
			padded--;	/* decrease assumed $decimal_point */
	}

	/* do padding with pad_char */
	if (padded > 0) {
		bufend -= padded;
		memset(bufend, pad_char, (size_t) padded);
	}

	bufsize = bufsize - (bufend - rslt) + 1;
	memmove(rslt, bufend, bufsize);
	free(avalue);
	return (rslt);
}